Q: When do you think it's safe to plant tomatoes? Could you tell me what to do to get a good crop?

B.D., Houston

A: We have had a consistently chilly winter, and Monday's dip into the 20s may have been a setback for risk-takers who planted tomatoes in February. But if the 10-day forecast doesn't include a freeze, you should be able to plant this most popular vegetable in a sunny, well-prepared bed during the next week or two. Just keep row covers for frost protection handy in case of another weather surprise.

Today's garden calendar on Page E4has several events that will offer a good selection of tomato varieties. Several nurseries also are well supplied. Select stocky, quick-maturing, disease-resistant types, and plant soon so they can grow and produce before it gets hot. Fruit sets when night temperatures are 50 to 70 degrees and days are 60 to 85 degrees. Many slicing tomatoes won't produce when night temperatures rise above 72 degrees and day temperatures hit 92 degrees. Cherry tomatoes may continue fruiting in the heat.

Tomatoes are best in eight hours of sun and in raised beds or rows of well-draining, organically enriched soil that provides abundant nutrients. Plant tomatoes in a different area than the previous year, if possible.

Related

Work 6 to 8 inches of compost into the soil before planting. Add two cups (1 pound) of a 15-5-10 or a 13-13-13 fertilizer per 50 square feet. Cottonseed meal, fish meal and molasses are popular organic additives.

Plant tomatoes deeper than they're growing in the nursery pots. Pinch off leaves that will be underground. New roots will develop along the buried stems and help feed and support the eventual extra-heavy plant tops.

Space the plants about 4 feet apart to provide growing room and better air circulation, which will discourage disease. Place heavy-duty cages over young plants so they will have support as they grow. Veteran tomato gardeners often wrap cages with row cover to keep insects and airborne diseases from young plants while allowing water and light to penetrate. Remove the row cover when the plants have grown to the cage tops.

Provide nutrition early: Water the transplants with a diluted seaweed and fish emulsion solution according to the label. Add a tablespoon of molasses per gallon of solution.

Keep the soil evenly moist. Dry conditions stress plants; so does soggy dirt. Drip or soaker irrigation systems place water at the root zone and avoid wetting the foliage, which can make it susceptible to disease.

Gardening

Fertilize when you see the first tiny tomatoes. Continue applications every week or two through the growing season.

Spray the foliage weekly with a diluted seaweed and fish emulsion solution to provide continuous nutrients.

Q: When can we tell whether our hibiscus plants survived the winter?

R.G., Houston

A: Once the weather is consistently warm, watch for new growth at the plants' bases and along the lower parts of the branches. Then cut back to the new green. You may need to prune an entire dead top. If no leaves appear by mid April, you may have lost your plants. Cold-hardiness depends on hibiscus type; unprotected tropical hibiscus may have died during the hard freezes. Root-hardy types will regrow at some point.

Q: We planted red 'Apeldoorn' tulips with good results for three years. Last year, when we switched to golden 'Apeldoorn,' trouble began; it has worsened this year. Whenever a flower is fully formed and ready to open, the next morning we find it on the ground, neatly severed from its stem. The flower is completely intact - no bruises, cuts, gnaw marks or missing petals. Last year, we lost two out of 100 tulips; this year, every tulip attempting to bloom has been severed. The severed flowers are usually near the beheaded plant. However, on one occasion, we found several flower heads about 8 feet away in a grassy spot on the other side of a wrought-iron fence.

We have the usual collection of birds, squirrels, possums and at least one raccoon. We're stumped. Do you have any suspects or recommendations?